meter barriga

1.
SpainLatin Americaliteralinformal
- Literally, to put or push the belly in a particular position.
2.
SpainLatin Americacolloquialinformal
- To suck in or hold in one's stomach in order to appear slimmer or to improve one's posture or appearance.

Examples:

ES: Y, uh, ¿a qué musculitos has elegido para meter barriga y sonreír al pajarito?
EN: So, uh, which hunky jock did you select to drop trou and smile for the birdie?
ES: Voy a tener que afeitarme cada día, meter barriga, tirar de la cadena.
EN: I'm gonna have to shave every day, suck in my gut, flush.
ES: Siempre intento meter barriga para lucir mejor.
EN: I'm always trying to suck in my motherfucking gut so I can look the best I can.
ES: Tengo que meter barriga, pero todo bien.
EN: I have to hold in my stomach, but that's OK.